1. Just format a USB falsh drive in FAT32.
2. Create a folder named: LG_DTV
3. Copy the firmware file inside the folder LG_DTV
4. Insert the USB on TV
5. Press install
6. Check on TV settings, general, about TV. You will see the firmware being installed, just like normal download over the internet.
7. When finished, turn off the TV and then turn it back on.